Microplaastics as potential bisphenol carriers: role of adsorbents, adsorbates, and environmental factors

Potent and Versatile Biogenically Synthesized Alumina/Nickel Oxide Nanocomposite Adsorbent for Defluoridation of Drinking Water

In the present work, an extract of Salvia officinalis leaves was used to synthesize an alumina/NiO nanocomposite by the coprecipitation method. First, the shape and surface content of the synthesized adsorbent were determined. Scanning electron microscopy images showed the production of nanospheres and nanorods with sizes between 35 and 50 nm. X-ray diffraction measurement revealed strong, high-intensity peaks, confirming the preparation of a highly crystalline alumina/nickel oxide nanocomposite. Then, the pure nanoalumina, nickel oxide, and functionalized alumina/nickel oxide nanocomposite for water defluoridation were investigated under various conditions, for example, stirring period, pH, and initial fluoride concentration. Defluoridation with greener alumina, nickel oxide, and alumina/nickel oxide nanocomposite lasted 120 min at adsorbent dosages of 0.8 g/L in a pH 7 solution. The adoption process for the three sorbents matches the Langmuir adsorption isotherm. The process dynamics were explored using pseudo-second-order and first-order kinetics. The water quality after treatment met drinking water requirements, proving the viability of using nanoparticles for drinking water defluoridation. This work confirmed effective water defluoridation in the crystalline phase using synthesized nanoalumina, nickel oxide, and their nanocomposite, which highlights their importance for future drinking water defluoridation.

Microplastics derived from plastic mulch films and their carrier function effect on the environmental risk of pesticides

Plastic film mulching can maintain soil water and heat conditions, promote plant growth and thus generate considerable economic benefits in agriculture. However, as they age, these plastics degrade and form microplastics (MPs). Additionally, pesticides are widely utilized to control organisms that harm plants, and they can ultimately enter and remain in the environment after use. Pesticides can also be sorbed by MPs, and the sorption kinetics and isotherms explain the three stages of pesticide sorption: rapid sorption, slow sorption and sorption equilibrium. In this process, hydrophobic and partition interactions, electrostatic interactions and valence bond interactions are the main sorption mechanisms. Additionally, small MPs, biodegradable MPs and aged conventional MPs often exhibit stronger pesticide sorption capacity. As environmental conditions change, especially in simulated biological media, pesticides can desorb from MPs. The utilization of pesticides by environmental microorganisms is the main factor controlling the degradation rate of pesticides in the presence of MPs. Pesticide sorption by MPs and size effects of MPs on pesticides are related to the internal exposure level of biological pesticides and changes in pesticide toxicity in the presence of MPs. Most studies have suggested that MPs exacerbate the toxicological effects of pesticides on sentinel species. Hence, the environmental risks of pesticides are altered by MPs and the carrier function of MPs. Based on this, research on the affinity between MPs and various pesticides should be systematically conducted. During agricultural production, pesticides should be cautiously selected and used plastic film to ensure human health and ecological security.

Microplastics in the Asia-Pacific Region in the Plasticene Era: Exposures and Health Risks

Within the broader Anthropocene Epoch resides the Plasticene Era, where humans are subjected pervasively to nano- and microplastics (NMPs). Human's widespread exposure with NMPs occurs through the air we breathe, water we drink, and food we eat. NMP sources are wide and varied; atmospheric NMPs are largely attributed to fibres from car tyres and synthetic clothing, while particles from food packaging, personal care products, and plastic manufacturing contribute significantly to food and water contamination. NMPs have become inherent within the human body and have been found in every organ. As such, the evidence base around adverse health effects is fragmented but growing. This article presents a mini-review and report of sessions presented about NMPs at the 19th International Conference of the Pacific Basin Consortium for Environment and Health, held on Jeju Island, in 2022. Abundant evidence of substantial exposure to NMPs in the Asia-Pacific region has been exhibited. Addressing this issue necessitates the collaboration of policymakers, manufacturers, and researchers to develop safer alternatives and implement mitigation and remediation strategies. The ongoing development of a new United Nations-led global plastic treaty presents a crucial opportunity that must be acted on and not be compromised.